There is normal signal, size and configuration of the brain parenchyma and CSF-containing spaces. There is no mass involving the bilateral IAC. Incidental note is made of a simple choroid or arachnoid cyst within the right lateral ventricle. There is no infarct, hemorrhage, hydrocephalus, mass-effect, space-occupying lesion, or pathologic fluid collection. The calvarial bone marrow signal is normal. No dural sinus thrombosis. The sella and craniocervical junction are normal.

High-resolution axial images through the posterior fossa demonstrate the internal auditory canals be symmetric in caliber. There is no mass within the internal auditory canal. The cerebellopontine angles are clear.

There is round, 7 mm T2 signal without restricted diffusion or susceptibility artifact within the right posterior, inferior mastoid bone likely representing a small effusion.

Magnetic resonance angiography

The intracranial internal carotid arteries are normal in caliber and signal intensity and give rise to normal bilateral anterior middle cerebral arteries.

Incidental note is made of normal variant low origin of the left PICA. The left PICA is dominant and is a congenital variant where the AICA arises from the PICA artery. There is incidental artifactual signal of a vein adjacent to the left internal auditory canal. The intracranial vertebral arteries are nearly symmetric and terminate in a normal basilar artery and posterior fossa branches. There is no aneurysm, flow-limiting disease, or evidence to suggest vascular malformation. Specifically, the basilar artery is normal in caliber with no evidence of intracranial stenosis